Showing posts with label ocean acidification; climate change. Show all posts
Showing posts with label ocean acidification; climate change. Show all posts

Monday, April 27, 2009

Reasons to doubt Plimer

Plimer unbloodied and certainly unbowed | Herald Sun Andrew Bolt Blog

Andrew Bolt thought that last Friday's debate on Radio National didn't hurt Plimer at all. I must admit, I didn't think that Veron was very effective, but then again, as he only had the book for an hour before the exchange, you couldn't expect him to be well informed on its contents.

But the main problem was that (as I understand it) Veron is an expert on reefs, which gives him an interest in global warming, but doesn't really make him a direct expert on climate science.

One thing of note did come out, however, and that is that it appears (as I suspected) that Plimer leaves ocean acidification pretty much out of the debate. (Veron said he had trouble finding any references to it, but eventually did find a brief mention.)

Anyway, a much better refutation of Plimer's book, at least in one specific field, was on Radio National this morning. You can listen to it here.

Tim Lambert already has his list of obvious faults or omissions, and a more recent post indicating a sarcasm misfire that appears in the book.

While we are still waiting to see a more detailed review from some experienced climate scientists, I don't see any reason as to why skeptics should think that this book represents any form of breakthrough.

UPDATE: Andrew Bolt hasn't commented on this story from last week, as far as I know, but it's one that seems worthy of the attention of any AGW skeptic who wants to be taken seriously.

Tuesday, April 21, 2009

Oceans and Plimer

Most Australian readers would probably know already of the global warming skeptics excitement about a new hefty book by geologist Ian Plimer that (apparently) sets out with lots of footnotes his opinion as to why the great majority of climate scientists are wrong.

While we are waiting for some climate scientist types to review it in detail, I am curious as to whether he makes any attempt at addressing ocean acidification. As remarked here many times, this is an issue skeptics just like to wave away with a few dismissive snorts, and that's about the extent of their analysis. (Yes, I am aware of Plimer's previous short contributions to the issue, such as this one noted last year at Marohasy's blog. Anyone who has bothered to read about the issue can readily spot that this was a disingenuous attempt at dismissing it, and does not address the reasons why it is believed to be a serious problem regardless of the oceans surviving past periods of high atmospheric CO2.)

In fact, I haven't posted anything new about ocean acidification for a few weeks, but there have been quite a few papers of note, such as:

* some new calculations indicate that ocean "dead zones" will increase:
increases in carbon dioxide can make marine animals more susceptible to low concentrations of oxygen, and thus exacerbate the effects of low-oxygen "dead zones" in the ocean.

Brewer and Peltzer's calculations also show that the partial pressure of dissolved carbon dioxide gas (pCO2) in low-oxygen zones will rise much higher than previously thought. This could have significant consequences for marine life in these zones.
* (if I am reading this right) some lab tests indicate that phytoplankton in nutrient poor ocean areas (such as the Southern Oceans, which will be affected first by lower .pH) don't do well with increased CO2.

* A paper notes the wildly conflicting results of different lab tests on whether a certain type of phytoplankton will get heavier or lighter with more ocean acidification. However, even if they do in nature get heavier, they will not make a significant reduction in CO2 levels in the atmosphere:
...it should be recognized that the direct impact of calcification changes on atmospheric CO2 through the remainder of this century is relatively small compared to anticipated annual emissions as well as to other carbon cycle feedbacks.
(Hence, if AGW is true, you can't expect the carbon incorporating phytoplankton to save you.)

* more research indicating pteropods (which feed a lot of fish) don't do well with increased acidfication. The researchers note:
A decline of their populations would likely cause dramatic changes to the structure, function and services of polar ecosystems.
Not exactly cheery news.

Friday, April 17, 2009

Forests not always so helpful

Dying trees may exacerbate climate change : Nature News

I have to reproduce a large part of this, because of Nature's silly way of putting stories under a paywall after a short time:

Forestry experts have again warned that climate change could transform forests from sinks to sources of carbon. The carbon storing capacity of global forests could be lost entirely if the earth heats up 2.5° Celsius above pre-industrial levels, according to a new report...

In a warmer world, subtropical and southern temperate forests such as those in the western United States, northern China, southern Europe, the Mediterranean and Australia will experience more intense and frequent droughts, increasing the incidence of fire and pests. This would lead to more carbon being released — a recent report in Science2 found that a 2005 drought in the Amazon basin released about 1.2 billion–1.6 billion tonnes of carbon (See 'Climate change crisis for rainforests').

The coniferous forests of Canada, Finland, Russia and Sweden that make up the boreal region are expected to experience more warming than forests in the equatorial zone. Although warmer temperatures could initially fuel a northward expansion of the forest, the short-term positive impacts would be cancelled out by damage from increased insect invasions, fires and storms.

The shift from sink to source is already happening. The mountain pine beetle has devastated the forests of western Canada. The outbreak currently covers 14 million hectares — roughly 3.5 times the size of Switzerland, says Allan Carroll, an insect ecologist with the Canadian Forest Service in Victoria, British Columbia. By 2020, the projected end of the outbreak, about 270 megatonnes of carbon will have been emitted to the atmosphere3. "That's the equivalent of five years of emissions from the entire transportation sector in Canada," says Carroll.

Friday, March 13, 2009

The BBC on ocean acidification

BBC NEWS | Science & Environment | 'Coral lab' offers acidity insight

Go to the link to find a series of pages which provide a quite balanced treatment of the issue of ocean acidification.

As usual, the news is nearly all bad. (There are a couple of quasi-dissenting scientists noted, but still no one who seems to think the oceans and reefs are going to be OK.)

Monday, March 09, 2009

Time for your bad ocean acidification news of the week

Proof on the Half Shell: A More Acid Ocean Corrodes Sea Life: Scientific American

The shells of tiny ocean animals known as foraminifera—specifically Globigerina bulloides—are shrinking as a result of the slowly acidifying waters of the Southern Ocean near Antarctica. ...

The researchers found that modern G. bulloides could not build shells as large as the ones their ancestors formed as recently as century ago. In fact, modern shells were 35 percent smaller than in the relatively recent past—
Not encouraging.

Wednesday, February 25, 2009

Back to ocean acidification, greenhouse gas, etc

Here's a round up of interesting stuff about greenhouse issues, all in one post so that readers who don't believe in it can skip right over!

* There's a study out on Great Barrier Reef coral which indicates ocean acidification (lowering of the ocean pH) has already been underway for some time. (Seems very technical work, and I wouldn't be surprised if other scientists argue about this.)

* It seems that at least some molluscs get heavier shells with more CO2 in the water, rather than lighter. This paper is based on some tank experiments, and is pretty noteworthy because it seems to show how little is properly understood about the biological processes in calcification.

The authors note, however, that heavier shell production (or just normal shell production) in some species seems to be at a price. (Like less muscle, reproductive changes.) It's still not a very encouraging sign that everything is OK under increased ocean acidification. (In fact, I seem to recall some article that was about a period in prehistory when molluscs ruled the oceans. Must go looking for that.)

* Ross Gittens writes this morning about the Rudd ETS and Penny Wong's recent counterattack on the idea that individual efforts to "reduce carbon footprint" don't change emissions overall. Ross says Rudd and Wong are being misleading in their claims:
It's true only in an arithmetic sense that anything we do "contributes directly" to Australia meeting its emissions target. Everything contributes to the bottom line of the sum. But, because the bottom line is controlled under the scheme, any helpful contribution we might make just leaves more scope for others to make unhelpful contributions.

When Wong says strong actions on our part help make it easier for governments to set lower emissions targets in future, the future she means is after 2020. As it stands, the only changes governments can make under the scheme are to the "trajectory" or path we travel to get to an unchanged destination level of emissions in 2020.

Why has the Government constructed its scheme in such a strange, off-putting way, which fact it has then wanted to conceal and obfuscate?

So, the point that individual actions to live more frugally leaves more room for industry to increase CO2 is correct.

(As I understand it, a carbon tax can't be really based on a set target, so there is a degree of guesswork involved in knowing where to set the tax so as to achieve a desired level of reduction. However, monitoring its progress should be a much simpler task, I would have thought; and you remove a lot of the "money for nothing" aspects of permit trading and derivatives markets that make me so sceptical of ETS as a concept.)

* I asked over at Harry Clarke's blog last night, but don't know the answer yet. Has anyone done any extensive work on how a carbon tax would work? ETS has been in favour for so long, I don't think there has ever been much in the way of discussion in the popular media about how you could make a carbon tax work.

My assumption had been that a carbon tax would mean each country concentrates on assessing it's own emissions, and the effect the tax is having on them. However, I suppose it is possible to have a system of credits involved too, and if credits could be gained for overseas offsets, you would have much of the same rorting possible as has been shown under the present European ETS.

Friday, February 20, 2009

Complicated

Carbon Capture Firm Could Use the Ocean to Combat Global Warming

I guess if money and energy are no object, there are lots of ways you can fiddle with the environment:

The study, "Electrochemical Acceleration of Chemical Weathering as an Energetically Feasible Approach to Mitigating Anthropogenic Climate Change," lays out a means of making the ocean more alkaline by reducing its acid content, in a process "equivalent to the electrochemical acceleration of the Earth's natural chemical weathering process."

In essence, the study proposes using electrolysis to convert weaker carbonic acid in the oceans into hydrochloric acid - "the engineered process accelerates the weathering kinetics to industrial rates," the study states. That could speed the rate at which silicate rocks –basalt, granite and other minerals that make up most of the Earth's crust – absorb the acid from the ocean.

"The increase in ocean alkalinity resulting from the removal of HCl causes atmospheric CO2 to dissolve into the ocean where it will be stored primarily as HCO3 without further acidifying the ocean," the study states. Atmospheric carbon dioxide is being absorbed by the ocean already, causing it to become more acidic - and that is leading to problems for coral reefs, giant squid and other ocean life, scientists say.

I think I have heard of this before, but not posted about it. Probably because of this:

Undertaking such a vast engineering project would be daunting, to be sure. It's the equivalent of building about 100 plants the size of major sewage treatment facilities to capture about 3.7 gigatons of carbon dioxide per year, the study states.

"Our current estimates indicate that running the process described here at scales sufficiently large to impact the earth's climate is unlikely to be commercially viable in the near future," the study says.

Wednesday, February 04, 2009

Un-informed

Ocean Acidification and Corals - Watts Up With That?

Watts Up With That has become a favourite blog for global warming sceptics, often quoted by Andrew Bolt, Jennifer Marohasy, etc. (I see Jennifer is away for an undefined period; probably to seek a credibility transplant after some of her recent efforts.)

But Watt's Up is spreading its wings to encourage scepticism about ocean acidification, with the above "guest post" by Steven Goddard.

It is, without doubt, the most starkly uninformed sceptical post about ocean acidification I have even seen at a blog that likes to credit itself as having a scientific attitude.

Monday, January 26, 2009

Bad ocean forecast of the week

Dramatic expansion of dead zones in the oceans

From the above report at PhysOrg:
A team of Danish researchers have now shown that unchecked global warming would lead to a dramatic expansion of low-oxygen areas zones in the global ocean by a factor of 10 or more.
The New Scientist version of the story adds this detail:

Under the worst-case scenario, average ocean oxygen levels will fall by up to 40%, and there will be a 20-fold expansion in the area of "dead zones", like those already discovered in the eastern Pacific and northern Indian Ocean, where there is too little oxygen for fish to survive. Even in the mid-range scenario, dead zones would expand by a factor of 3 or 4. Cold, deep waters will also be affected if warming stifles the currents that deliver oxygen to greater depths.

Shaffer's projections suggest that the oxygen content in surface layers will dip to its lowest levels during the 22nd century, and in deep water a thousand years later. Recovery to pre-industrial levels will be very slow: "Even after 100,000 years, oxygen levels will only have recovered by around 90%," he says.


Go to the links for more details. Not exactly encouraging, as it shows what is potentially at stake if the warming skeptics are wrong. (And it is an additional risk to that of ocean acidification, which of itself is a major concern for future ocean health.)

Sunday, January 04, 2009

Back to the serious stuff

AIMS Media Release January 2, 2009

It’s official: the biggest and most robust corals on the Great Barrier Reef (GBR) have slowed their growth by more than 14 per cent since the "tipping point" year of 1990. Evidence is strong that the decline has been caused by a synergistic combination of rising sea surface temperatures and ocean acidification.

A paper* published today (Friday 2 January 2009) in the prestigious international journal Science and written by AIMS scientists Dr Glenn De’ath, Dr Janice Lough and Dr Katharina Fabricius is the most comprehensive study to date on calcification rates of GBR corals...

On current trends, the corals would stop growing altogether by 2050.

"The data suggest that this severe and sudden decline in calcification is unprecedented in at least 400 years," said AIMS scientist and principal author Dr Glenn De’ath.

And here I was thinking that the Americans had cornered the market in really strange surnames.

But I shouldn't make light of him: it sounds as if his work is a pretty significant milestone for showing that the Great Barrier Reef really is in serious trouble. (And as for the ocean acidification component, it will happen regardless of air temperature.)

By the way, Tim Blair and his readers seem to take profound pleasure in their ignorance lately, when it comes to ridiculing any and all geoengineering concepts for dealing with CO2. For example, iron fertilization of the oceans as an idea has been around for a long time, and has often been discussed in popular science magazines like Discover or New Scientist. Sure, many scientists are sceptical of it being a good idea, but it has been tried on a small scale, and calling it the equivalent of a madman's idea is just displaying ignorance. It also shows an attitude more appropriate for a certain class of annoying self centred teenager, where ridicule is the easier option than actually trying to understand something. (Overly idealist teenagers who think they will change the world overnight are also annoying in their own way, as Blair knows.)

As with Andrew Bolt, Tim shows no sign of even a vague attempt at informing himself as to the real issues of climate change and ocean acidification, and just accepts any skeptical opinion with open arms. (He recently provided a link to "electric plasma" fan Louis Hissink, a well known climate skeptic at Jennifer Marohasy's. His fondness for Velikovsky's eccentric - although admittedly fun to contemplate - ideas puts him well outside the geologists' mainstream. )

I've said it before and will say it again: taking shots at exaggerations and media reporting on the "warminist" side is one thing, as is scepticism that carbon trading is going to work, or that the answer lies in a few million windmills.

But don't throw the baby out with the bathwater.

Tuesday, December 16, 2008

Squid lovers take note

Rise in CO2 'affects jumbo squid'

Ocean acidification is likely to make jumbo squid unhappy.

Well, good to see that squid lovers of the world will at last be convinced to take ocean acidification seriously.

Friday, December 05, 2008

Your weekly ocean acidification news

Comment on "Phytoplankton Calcification in a High-CO2 World" -- Riebesell et al. 322 (5907): 1466b -- Science

Readers interested in my ocean acidification posts* will recall that there was a big surprise earlier this year when one study suggested that one species of calcifying phytoplankton actually got substantially heavier with more CO2 in the water.

The suggestion was that this may work as an important new CO2 sink, and was quite contrary to previous studies which showed the coccolithophore shells getting smaller with increased ocean acidity.

There was some muttering at the time by other scientists that this study could have been flawed, and now, see the link for a detailed comment by a group of scientists who think they have the problems with the experiment.

The comment is worth reading as setting out the basic issues with acidification and calcification.

Basically, this group still sounds very pessimistic about the "winners" outweighing the "losers" in ocean acidification.

* and who knows if there are any? - no one ever comments on those posts, which just encourages me to continue grinding my teeth about how most of the world is ignoring this issue.

Monday, December 01, 2008

Complicated oceans

North Atlantic cold-water sink returns to life : Nature News

Here's the opening paragraph from the above report:
Scientists have found evidence that convective mixing in the North Atlantic, a mechanism that fuels ocean circulation and affects Earth's climate, has returned after a decade of near stagnation – thanks, perhaps, to a dramatic loss of sea-ice in the Arctic during the summer of 2007.
From a global warming/greenhouse gas point of view, this appears to be good news. Certainly, the oceans are proving remarkably complicated to understand, probably because they are huge and hence hard to study:

Reduced convection should in theory weaken the entire Atlantic meridional overturning circulation (MOC) — responsible for carrying warm tropical water northwards — with far-reaching consequences for Earth's climate. But so far at least, scientists have not observed any significant changes to that large-scale circulation. Findings published in 2005 that seemed to indicate a big slowing of the MOC were later found to be in the range of natural fluctuations (see 'Ocean circulation noisy, not stalling').

One reason, says Fischer, is that the observational basis is still thin. The Argo programme, a global array of 3,000 robots that measure temperature, salinity and water pressure, has only last year become fully operational, for example.

But already it's clear that the response of the Atlantic Ocean circulation to high-latitude changes is much more complex than has been assumed.
(And by the way, I don't know that this has much influence on the issue of ocean acidification as a concern.)

Tuesday, November 25, 2008

Your next weekly dose of bad ocean news

BBC NEWS | Science & Environment | Marine life faces 'acid threat'

Man-made pollution is raising ocean acidity at least 10 times faster than previously thought, a study says.

Researchers say carbon dioxide levels are having a marked effect on the health of shellfish such as mussels.

They sampled coastal waters off the north-west Pacific coast of the US every half-hour for eight years.

The results, published in the journal PNAS, suggest that earlier climate change models may have underestimated the rate of ocean acidification.
To be fair, some reported comments of one of the researchers involved are misleadingly expressed:
"Many sea creatures have shells or skeletons made of calcium carbonate, which the acid can dissolve," said Catherine Pfister, Associate Professor of Ecology and Evolution at the University of Chicago and a co-author of the study.
That could easily be taken to mean the ocean is actually turning into an acidic pH, but ocean acidification at its worst will still leave the ocean alkaline (just significantly less alkaline than it used to be.)

Anyhow, it's still bad news, by any interpretation.

Tuesday, November 18, 2008

Your weekly dose of bad ocean news

Marine dead zones set to expand rapidly : Nature News
Rising levels of carbon dioxide could increase the volume of oxygen-depleted 'dead zones' in tropical oceans by as much as 50% before the end of the century — with dire consequences for the health of ecosystems in some of the world's most productive fishing grounds....

A team led by Andreas Oschlies of the Leibniz Institute of Marine Sciences in Kiel, Germany, has now used a global model of climate, ocean circulation and biogeochemical cycling to extrapolate existing experimental results of the effects of altered carbon and nutrient chemistry on dissolved oxygen to the global ocean1. They found that a CO2-rich world will only have a small impact on waters at middle and high latitudes. But in all tropical oceans the volume of 'oxygen-minimum' zones will substantially increase as ocean bacteria feed on the algae that will flourish as a result of the elevated CO2 levels.

"Carbon dioxide fertilizes biological production," says Oschlies. "It's really like junk food for plants. When the carbon-fattened excess biomass sinks it gets decomposed by bacteria which first consume the oxygen, and then the nutrients."
In one of my earlier posts on ocean acidification, I had questioned whether algal blooms caused by more CO2 might be a bad thing for this very reason. (Some sceptics argue that more algae operating as a carbon sink will be a good thing. But obviously, it has a massive down side.)

Again, as far as I can see, this is an ocean danger story that is getting little press attention. Bah.

Thursday, October 30, 2008

Shrimp don't care for CO2

Long-term effects of predicted future seawater CO2 conditions on the survival and growth of the marine shrimp Palaemon pacificus

Another day, another report of an experiment in which a marine creature is shown to be adversely affected by high levels of CO2 in the atmosphere:
The present results demonstrate for the first time that the predicted future seawater CO2 conditions would potentially reduce shrimp, and possibly other crustacean, populations through negatively affecting mortality, growth, and reproduction. This could threaten entire marine ecosystem through disrupting marine food web.
News will be greeted by the sounds of crickets chirping in the audience.

Wednesday, October 29, 2008

UQ research on acidification and reefs

Rising CO2 'will hit reefs harder'

As usual with the issue of ocean acidification, this will probably just get 'spotty' media coverage:
In a large experiment on Heron Island, the team simulated CO2 and temperature conditions predicted for the middle and end of this century, based on current forecasts of the world's likely emission levels and warming by the Intergovernmental Panel on Climate Change (IPCC).

The results of their analyses of the bleaching, growth and survival of a number of organisms including corals indicates that a number of very important reef builders may be completely lost in near future.

“We found that coralline algae, which glue the reef together and help coral larvae settle successfully, were highly sensitive to increased CO2. These may die on reefs such as those in the southern Great Barrier Reef before year 2050,” says Dr Anthony.

Wednesday, October 22, 2008

Don't tell Andrew Bolt

Less Ice In Arctic Ocean 6000-7000 Years Ago

Andrew Bolt and others have been posting a lot about the Arctic ice melt (and apparent recent rapid re-freeze), so he's bound to take encouragement from this article that suggests that the Arctic ocean had much less ice 7,000 years ago too, before our modern CO2 increase, of course.

My general impressions are as follows:

* the issue of the coming and going of Arctic ice is clearly not fully understood.

* of course there are AGW advocates who leap too quickly onto anything that appears to prove greenhouse warming. Those who wildly overstate the case as to the short term effects of AGW (such as Tim Flannery, Al Gore, etc) are usually not the scientists themselves.

* most climate scientists were actually somewhat cautious in what they said about the big 2007 melt. At Real Climate, for example, they said:
The disappearance of the ice was set up by warming surface waters and loss of the thicker multi-year ice in favor of thinner single-year ice. But the collapse of ice coverage this year was also something of a random event. This change was much more abrupt than the averaged results of the multiple IPCC AR4 models, but if you look at individual model runs, you can find sudden decreases in ice cover such as this. In the particular model run which looks most like 2007, the ice subsequently recovered somewhat, although never regaining the coverage before the meltback event.
* even if the current round of substantially lower than average summer ice is caused by completely different cyclic factors from CO2 increase, it may be a worry if the cycle continues because of its potential to have an enhancing effect on any warming that is caused by CO2 in coming decades.

Methane coming out of the Arctic ocean may well end up being a major concern too. We will hear more about that soon, it seems.

* Above all, remember my official line is that ocean acidification is a big enough issue alone to limit CO2 anyway. Doesn't matter if temperatures go up or down: a huge gamble with what will happen to ocean ecology is in play if CO2 is allowed to soar to levels not seen for millions of years.

Wednesday, October 15, 2008

Fearing for krill (and penguins, whales, etc)

The krilling fields: study fears catastrophe in Antarctic food chain | theage.com.au

From the report:

Captive-bred krill at the Australian Antarctic Division developed deformities and lost energy when they were exposed to the greenhouse gas at levels predicted globally for the year 2100.

The damage meant that the krill were unlikely ever to breed, a University of Tasmania investigator, Lilli Hale, said yesterday.

Polar life, from tiny seabirds through penguins and seals to whales, depend for food on Antarctic krill, Euphasia superba.

I see that Tim Blair today has a short post up linking to a different ocean acidification story, pretty much as if it is the first time he has heard of the issue. I have said it before, but I don't understand why it is a topic that attracts very intermittent coverage, as it will happen whether or not the planet heats or cools. Tim's commenters all appear to be dismissive experts on the topic without actually having read much about it.

On the (perhaps slim) chance that Tim or his readers will follow my advice to look at it harder before pooh-poohing the idea, I link to this article again. Then they can get back to me when they find an actual ocean scientist who has looked at the issue and come up saying "nah, it's nothing to worry about." (Seafriends website does not count, as I have explained before.)

Thursday, August 28, 2008

Scientists worried

Scientists Unveil "Honolulu Declaration" To Address Ocean Acidification

Hey, ocean acidification skeptics, when we will get to see something like an Oregon Petition on this topic?